| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.1 | 1.3 | 0.89 |
| 2024 | 1.08 | 1.5 | 0.79 |
| 2023 | 1.62 | 2.1 | 1.15 |
| 2022 | 3.03 | 5.15 | 2.01 |
| 2021 | 6.27 | 11 | 3.51 |
| 2020 | 10.06 | 20.62 | 3.77 |
| 2019 | 4.32 | 6.53 | 3.46 |
| 2018 | 6.84 | 8.44 | 4.27 |
| 2017 | 9.43 | 12.18 | 7.99 |
| 2016 | 15.19 | 23.23 | 11.76 |
| 2015 | 29.44 | 50.09 | 13.64 |
| 2014 | 13.59 | 20.46 | 8.58 |
| 2013 | 7.84 | 11.25 | 5.53 |
| 2012 | 5.97 | 7.23 | 4.72 |
| 2011 | 8.31 | 11.08 | 6.04 |
| 2010 | 9.84 | 12.21 | 7.46 |
| 2009 | 9.1 | 13.2 | 4.57 |
| 2008 | 5.82 | 9.52 | 2.93 |
| 2007 | 6.52 | 9.88 | 3.4 |
| 2006 | 3.39 | 4.4 | 2.61 |
| 2005 | 3.32 | 4.09 | 2.68 |